Touring - Schwalbe tire sizing listings vs reality discrepancy

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.



PDA
AnnaMossity
07-23-08, 09:01 AM
Okay, I've got almost all the stuff I need for my touring bike but am stuck on tire selection.

Rivendell's website shows the Schwalbe Marathon XR 42-622 tire as having an actual width of 37.677mm at its widest point. 37.677mm is just a bit too wide for my bike. I was looking at the 37-622 and wondering if the tire sizing would also be around 5mm narrower than listed when it's on my bike because if so, that'll be a good fit for my bike frame. Anyone have these tires that can help me out?

I am so stoked about getting this thing built.

Cyclesafe
07-23-08, 01:28 PM
You might get a better response if you tell us what kind of frame you have, but I think you can assume that the 37-622 will be 5 mm narrower than the 42-622.

Of course, what's relevant is how wide the tire is with the bike loaded and with you sitting on it - not something Rivendell has any info about. You'll need ample clearance between the tire and your frame (also fender) for gravel and other flying debris, otherwise you can jam a wheel (especially the front) and crash. A 42 makes sense over a 37 only if your bike is carrying more than 250-280 lbs and/or you will be on worse surfaces than asphalt. A 42 is good to about 280-330.

If you and your loaded bike weigh 220 to 250 lbs and you'll only be on asphalt, I'd consider the Schwalbe Marathon Supreme in 32 mm. It would be everything you'd want in a touring tire and is 140g lighter than the 42-622 XR.

http://schwalbetires.com/marathon_supreme
AnnaMossity
07-29-08, 08:30 AM
Well I have an '83 Kuwahara/Apollo Prestige XL frame. Not much clearance. Good point about the rocks jamming in the bike frame. I'll have to watch out for that.

I'm 171lbs and not sure how much weight I'll be carrying but I can make it under 250 if need be. I'll probably have less than 1cm clearance on either side of the front forks and less between the chain stays. I'm going to Brazil for 2 months on this bike so that'll involve some dirt roads and maybe some easy off roading. It might be sketchy but I'm not going to let lack of funds get in my way.

Wound up ordering the Marathon XR 37-622, but only one. This way I can probably just trade it for a narrower set of tires if it's too wide.

Thanks for your help.